<template>
  <div>
    <router-link tag="div" to="/" class="header-abs" v-show="showAbs">
      <div class="iconfont header-abs-back">&#xe624;</div>
    </router-link>
    <div class="header-fixed" v-show="!showAbs" :style="opacityStyle">
      <router-link to="/">
        <div class="iconfont header-fixed-back">&#xe624;</div>
      </router-link>
      景点详情
    </div>
  </div>
</template>

<script>
export default {
  name: 'DetailHeader',
  data () {
    return {
      showAbs: true,
      opacityStyle: {
        opacity: 0
      }
    }
  },
  methods: {
    handleScroll () {
      console.log('scroll')
      const top = document.documentElement.scrollTop
      if (top > 60) {
        let opacity = top / 140
        opacity = opacity > 1 ? 1 : opacity
        this.opacityStyle = { opacity }
        this.showAbs = false
      } else {
        this.showAbs = true
      }
    }
  },
  mounted () {
    window.addEventListener('scroll', this.handleScroll)
  }
  // activated () {
  //   console.log('activated')
  //   window.addEventListener('scroll', this.handleScroll)
  // },
  // deactivated () {
  //   console.log('deactivated')
  //   window.removeEventListener('scroll', this.handleScroll)
  // }
}
</script>

<style lang="stylus" scoped>
@import '~styles/varibles.styl'

.header-abs
  position: absolute
  left: 0.2rem
  top: 0.2rem
  width: 0.8rem
  height: 0.8rem
  line-height: 0.8rem
  border-radius: 0.4rem
  text-align: center
  background: rgba(0, 0, 0, 0.8)
  z-index: 1

  .header-abs-back
    color: #fff
    font-size: 0.4rem

.header-fixed
  z-index: 2
  position: fixed
  top: 0
  left: 0
  right: 0
  height: $headerHeight
  line-height: $headerHeight
  text-align: center
  color: #fff
  background: $bgColor
  font-size: 0.32rem

  .header-fixed-back
    position: absolute
    top: 0
    left: 0
    width: 0.64rem
    text-align: center
    font-size: 0.4rem
    color: #fff
</style>
